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Math: Basic Tutorials : Fractions

Understanding Fractions


Fractions are essential for performing accurate calculations in healthcare. A fraction represents a part of a whole and is expressed as a numerator (the part) over a denominator (the whole). Understanding fractions and their different forms—proper, improper, and mixed—helps you handle a variety of clinical scenarios with ease.

This section will explore the different forms of fractions and how to switch between them, making it easier to perform operations in different contexts. Additionally, we’ll cover arithmetic operations with fractions, including addition, subtraction, multiplication, and division, all of which are critical for accurate medication calculations and other healthcare tasks.

Proper Fractions

A proper fraction is a fraction whose numerator is smaller than its denominator. For example:

12or45or37


Improper Fractions

An improper fraction is a fraction whose numerator is greater than its denominator. For example:

32or74or95


Mixed Fractions

A mixed fraction or mixed number is a combination of a whole number and a proper fraction. For example:

312or525or134


Note: the shaded region in the circles representing 74 from 'improper fractions' and 134 are the same. In fact, 134=74

They are different ways of representing the same thing!

Switch from Mixed to Improper Fractions

To switch from mixed to improper:

  1. Multiply the whole number by the denominator of the proper fraction
  2. Add to the numerator of the proper fraction.

Switch from Improper to Mixed Fractions

To switch from improper to mixed:

  1. Use long division to divide the denominator into the numerator.
  2. We will use the Quotient and Remainder to write our Mixed Fraction.

The improper fraction in mixed form is: Quotient RemainderDenominator

Adding and Subtracting Fractions

To add/subtract fractions:

  1. Make sure the denominators are the same.**
  2. Add/Subtract the numerators and put that answer over the denominator.
  3. Simplify the fraction if necessary.
    • This is done by dividing numerator and denominator by their Greatest Common Factor (GCF).

**If they are not, this can be done by rewriting one/both of the fractions by multiplying both numerator and denominator by the same value. For example:

12 is the same as 24 because 12=1×22×2=24

Note: For simplicity, we aim to multiply both fractions separately to ensure each denominator becomes the least common multiple (LCM) of the two original denominators.


Click on the titles below to view each example.

Multiplying Fractions

To multiply fractions:

  1. Multiply the numerators together.
  2. Multiply the denominators together.
  3. As always, simplify if necessary.

Note: remember the rule "Top by top, Bottom by bottom".


Dividing Fractions

To divide fractions:

  1. Change the division symbol to a multiplication symbol.
  2. Flip the divisor.
    • The divisor is the dividing fraction in this case, like 12 in 34÷12
  3. Perform the multiplication, and as always, simplify if necessary.

Note: remember the rule "Keep, Change, Flip".